Holstein (n = 19) and Jersey (n = 18) cows were used to study effects of two feeding systems on fatty acid composition of milk. Confinement cows were fed a total mixed ration with corn silage and alfalfa silage and pastured cows grazed a crabgrass (90%) and clover (10%) pasture and were allowed 5.5 kg of grain per head daily. Two milk samples were collected from each cow at morning and afternoon milkings 1 d each week for four consecutive weeks in June and July 1998. One set of milk samples was analyzed to determine fatty acid composition, and the second set was used for crude protein and total fat analyses. Data were analyzed by the general linear models procedure of SAS, using a split-plot model with breed, treatment, and breed x treatment as main effects and time of sampling and week as subplot effects along with appropriate interactions. Milk from pastured cows was higher than milk from confinement cows for the cis-9, trans-11 octadecadienoic acid isomer of conjugated linoleic acid (CLA). Also, milk from Holsteins was higher than milk from Jerseys for C16:1, C18:1, and CLA and lower than Jerseys for C6:0, C8:0, C10:0, C12:0, and C14:0. Several treatment x week interactions existed, but main effects were still important; for example, proportions of CLA in milk of grazed cows were relatively constant across weeks (0.66, 0.64, 0.64, and 0.69% +/- 0.02%, respectively), but the CLA in milk of confinement cows increased in wk 4 (0.35, 0.31, 0.31, and 0.48% +/- 0.02% for wk 1 to 4, respectively). There are potentially important differences in fatty acid composition of milk from cows consuming a warm season pasture species compared with milk from cows consuming a total mixed ration, as well as differences between Holstein and Jersey breeds.

A B S T R A C T Total and unbound testosterone and A4-androstenedione have been determined in 104 cord blood samples. The same sexual steroids and pituitary gonadotropins have been measured in 46 normal male infants aged 27-348 days and 34 normal female infants aged 19-332 days.In cord blood of female neonates mean total and unbound testosterone was 29.6±7.5 and 0.89±0.4 ng/100 ml, respectively (mean±l SD); A4-androstenedione was 93±38 ng/100 ml. In male neonates mean plasma total and unbound testosterone was 38.9±10.8 and 1.12±0.4 ng/100 ml; A'-androstenedione was 85±27 ng/100 ml.In female infants testosterone concentrations remained constant during the lst yr of life with a mean concentration of 7±3 ng/100 ml. Mean unbound testosterone and A'-androstenedione concentrations were 0.05±0.03 and 16.7±8.3 ng/100 ml, respectively. Mean plasma levels of follicle-stimulating hormone and luteinizing hormone were 8.7±3.3 and 12.9±7.7 mU/ml.In male infants mean plasma total testosterone concentration increased to 208±68 ng/100 ml from birth to 1-3 mo of age, decreasing thereafter to 95±53 ng/100 ml at 3-5 mo, 23.2±18 ng/100 ml at 5-7 mo, and reached prepubertal levels (6.6±4.6 ng/100 ml) at 7-12 mo.Mean unbound testosterone concentration plateaued from birth to 1-3 mo of age (1.3±0.2 ng/100 ml) decreasing to prepubertal values very rapidly. Mean A4-androstene-

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Congenital adrenal hyperplasia (CAH) is caused by disorders of the P450c21B gene, which, with the P45Oc21A pseudogene, lies in the HLA locus on chromosome 6. The near identity of nucleotide sequences and endonuclease cleavage sites in these A and B loci makes genetic analysis of this disease difficult. We used a genomic DNA probe that detects the P45Oc21 genes (A pseudogene, 3.2 kb; B gene, 3.7 kb in Taq leles thus can easily be classified with this new probing strategy, eliminating many ambiguities resulting from probing with cDNA.